This short Introduction into Space Charge E?ects in Semiconductors is designed for teaching the basics to undergraduates and show how space charges are created in semiconductors and what e?ect they have on the el- tric?eldandthe energybanddistributioninsuchmaterials, andconsequently on the current-voltage characteristics in semiconducting devices. Such space charge e?ects were described previously in numerous books, fromtheclassicsofSpenkeandShockleytothemorerecentonesofSeegerand others.Butmanymoredetailedinformationwereonlyavailableintheoriginal literatureandsomeofthemnotatall.Itseemstobeimportanttocollectallin a comprehensive Text that can be presented to students in Physics, Electrical Engineering, and Material Science to create the fundamental knowledge that is now essential for further development of more sophisticated semiconductor devices and solar cells. This book will go through every aspect of space charge e?ects and - scribe them from simple elementaries to the basics of semiconductor devices, systematically and in progressing detail. For simplicity we have chosen this description for a one-dimensional se- conductorthatpermitsasimpledemonstrationoftheresultsgraphicallywi- out requiring sometimes confusing perspective rendering. In order to clarify the principles involved, the book starts with a hy- thetical model, by assuming simple space charge distributions and deriving their e?ects on ?eld and potential distributions, using the Poisson equation. Itemphasizestheimportantsignrelationsoftheinterreactingvariables, space charge, ?eld, and potential (band edges). It then expands into simple semiconductor models that contain an abrupt nn-junction and gives an example of important space chargelimited currents, + as observed in nn -junction

"Nanostructure Semiconductor Optical Amplifiers" reviews all-optical processing methods currently available and presents semiconductor optical amplifiers (SOAs) as a new building block for this purpose. The authors discuss the overcomes of high frequency operation of SOAs and propose a new all-optical pumping method for the implementation of semiconductor optical amplifiers.

Semiconductor lithography is one of the key steps in the manufacturing of integrated silicon-based circuits. In fabricating a semiconductor device such as a transistor, a series of hot processes consisting of vacuum film deposition, oxidations, and dopant implantation are all patterned into microscopic circuits by the wet processes of lithography. Lithography, as adopted by the semiconductor industry, is the process of drawing or printing the pattern of an integrated circuit in a resist material. The pattern is formed and overlayed to a previous circuit layer as many as 30 times in the manufacture of logic and memory devices. With the resist pattern acting as a mask, a permanent device structure is formed by subtractive (removal) etching or by additive deposition of metals or insulators. Each process step in lithography uses inorganic or organic materials to physically transform semiconductors of silicon, insulators of oxides, nitrides, and organic polymers, and metals, into useful electronic devices. All forms of electromagnetic radiation are used in the processing. Lithography is a mUltidisciplinary science of materials, processes, and equipment, interacting to produce three-dimensional structures. Many aspects of chemistry, electrical engineering, materials science, and physics are involved. The purpose of this book is to bring together the work of many scientists and engineers over the last 10 years and focus upon the basic resist materials, the lithographic processes, and the fundamental principles behind each lithographic process.

The occurrence of superconductivity among the d- and f-band metals remains one of the unsolved problems of physics. The first Rochester conference on this subject in October 1971 brought together approximately 100 experimentalists and theorists, and that conference was considered successful; the published proceedings well-represented the current research at that time and has served as a "handbook" to many. In the four and one half years since the first conference, impressive progress has been made in many areas (although Berndt Matthias would be one of the first to point out that raising the m"aximum transition temperature by a significant amount was not one of them). For a variety of reasons, I decided that it was time for a Second Rochester Conference on Superconductivity in d- and f-Band Metals and it was held on April 30 and May 1, 1976. It would appear that this conference was even more successful judging from the quality of the talks and various comments made to me. I believe that this was due to the fact that the subject matter is exciting and that the timing was particularly appropriate for several areas of research that were discussed. However, I cannot rule out other factors such as the one advanced humorously by J.

Five years have passed since the breakthrough in the critical temperature for superconductors. During this period, many superconducting materials have been discovered and developed, and our knowledge of the physical and other properties of oxide superconductors has deepened through extensive and intensive research. This knowledge has advanced superconductivity science and technology from the initial questioning stage to a more developed but still uncertain second stage where research activity in superconductivity now overlaps with fields of application. Generally speaking, science resonates with technology. Science not only complements but also competes with or stimulates technology. New scientific knowledge has triggered the second technological research stage. Much progress has been made in the development of practical devices, encouraging the application of superconductors in areas such as human levitation, a high speed levitated bearing, large current transforming leads, and high frequency devices. This technological progress has increased our understanding of the science involved, such as flux pinning and dynamics, and anomalous long-range superconducting interactions. At this important stage, international cooperation and collaborative projects can effectively sustain aggressive research and development in order to advance superconductivity to the next stages. The ISS Symposium is expected to serve as a venue for increasing our knowledge of superconductivity and for exchanging visions for future research and applications, through the presentation and discus of the latest research results. These proceedings also aim to summarize sion annual progress in high-Tc superconductivity in all fields."

I am indeed pleased to prepare this brief foreword for this book, written by several of my friends and colleagues in the Soviet Union. The book was first published in the Russian language in Moscow in 1975. The phenomenon of superconductivity was discovered in 1911 and promised to be important to the production of electromagnets since superconductors would not dissipate Joule heat. Unfortunate ly the first materials which were discovered to be superconducting reverted to the normal resistive state in magnetic fields of a few tesla. Thus the development that was hoped for by hundredths of a the early pioneers was destined to be delayed for over half a century. In 1961 the intermetallic compound NbaSn was found to be superconducting in a field of about 200 teslas. This breakthrough marked a turning point, and 50 years after the discovery of superconductivity an intensive period of technological development began. There are many applications of superconductivity that are now being pursued, but perhaps one of the most important is super conducting magnetic systems. There was a general feeling in the early 1960s that the intermetallic compounds and alloys that were found to retain superconductivity in the presence of high magnetic fields would make the commercialization of superconducting magnets a relatively simple matter. However, the next few years were ones of disillusionment; large magnets were found to be unstable, causing them to revert to the normal state at much lower magnetic fields than predicted."

Inelastic Electron Tunneling Spectroscop or lETS, provides a unique technique for electronically monitoring the vibrational modes of molecul (;5 adsorbed on a metal oxide surface. Since the discovery of the phenomena by JAKLEVIC and LM1BE in 1966, lETS has been developed by a number of scientists as a method for studying the surface chemistry of molecular species adsorbed on aluminum oxide. Recent applications of lETS include investigations of physical and chemical adsorption of hydrocarbons, studies of catalysis by metal particles, detection and identification of trace substances in air and water, and studies of biological molecules and electron damage to such molecules. lETS has been employed to investigate adhesive materials, and studies are currently in prog ress to investigate corrosion species and corrosion inhibitors on aluminum and its alloys. Electronic transitions of molecules have also been studied by lETS. The recent development of the "external doping" technique, whereby molecu lar species can be introduced into fabricated tunnel junctions, opens the door for a vast new array of surface chemical studies by lETS. lETS is rap idly becoming an important tool for the study of surface and interface phe nomena. In addition to its role in surface studies, inelastic tunneling has proved extremely valuable for the study of the electronic properties of thin metallic films, and the recent discovery of light emission from inelastic tunneling promises to be of some importance in the area of device physics."

Quasicrystals are a new form of the solid state which differ from the other two known forms, crystalline and amorphous, by possesing a new type of long-range translational order, called quasiperiodicty, and a noncrystallographic orientational order. This book provides an up-to-date description of the unusual physical properties of these new materials. Emphasis is placed on the experimental results, which are compared with those of the corresponding crystalline and amorphous systems and discussed in terms of modern theoretical models. Written by leading authorities in the field, the book will be of great use both to experienced workers in the field and to uninitiated graduate students.

The Novel Mechanisms of Superconductivity Conference was initially conceived in the early part of 1986 as a small, 2-1/2 day workshop of 40-70 scientists, both theorists and experimentalists interested in exploring the possible evidence for exotic, non phononic superconductivity. Of course, the historic discoveries of high temperature oxide superconductors by Bednorz and Mftller and the subsequent enhancements by the Houston/Alabama groups made such a small conference impractical. The conference necessarily had to expand, 2-1/2 days became 4-1/2 days and superconductivity in the high Tc oxides became the largest single topic in the workshop. In fact, this conference became the first major conference on this topic and thus, these proceedings are also the first maj or publication. However, heavy fermion, organic and low carrier concentration superconductors remained a very important part of this workshop and articles by the leaders in these fields are included in these proceedings. Ultimately the workshop hosted rearly 400 scientists, students and media including representatives from the maj or research groups in the U.S., Europe, Japan and the Soviet Union.

Process Technology for Semiconductor Lasers describes the design principles of semiconductor lasers, mainly from the fabrication point of view. A review is given of the history of semiconductor-laser development and applications and of the materials used in lasing at short to long wavelengths. The basic design principles for semiconductor-laser devices and the epitaxy for laser production are discussed. An entire chapter is devoted to the technology of liquid-phase epitaxy, and another one to vapor-phase and beam epitaxies. The characterizations of laser materials and the fabrication and characteristics of semiconductor lasers are treated. Mode-control techniques are presented, and surface-emitting lasers are introduced in the final chapter.

The International Winter School on Electronic Properties of High-Temperature Superconductors, held between March 7-14, 1992, in Kirchberg, (Tyrol) Austria, was the sixth in a series of meetings to be held at this venue. Four of the earlier meetings were dedicated to issues in the field of conducting polymers, while the winter school held in 1990 was devoted to the new discipline of high-T c superconductivity. This year's meeting constituted a forum not only for the large number of scientists engaged in high-Tc research, but also for those involved in the new and exciting field of fullerenes. Many of the issues raised during the earlier winter schools on conducting polymers, and the last one on high-T c superconductivity, have taken on a new significance in the light of the discovery of superconducting C materials. 60 The Kirchberg meetings are organized in the style of a school where expe rienced scientists from universities, research laboratories and industry have the opportunity to discuss their most recent results, and where students and young scientists can learn about the present status of research and applications from some of the most eminent workers in their field. In common with the previous winter school on high-Tc superconductors, the of the cuprate superconductors. present one focused on the electronic properties In addition, consideration was given to related compounds which are relevant to the understanding of the electronic structure of the cuprates in the normal state, to other oxide superconductors and to fulleride superconductors.

In terms of structure, the field of semiconductors spans a wide range, from the perfect order of single crystals to the non-periodic, disordered amorph ous state. The two extremes of this range attract a large amount of inter est. On one side, glamorous novel phenomena are being found which can only occur in specially tailored ultra-perfect periodic lattices. On the other side, the exotic and challenging nature of the amorphous state has triggered a surge of activity in recent years. Po1ycrystall i ne semi conductors are in between. They are among the work horses in the field, useful in many applications, a handy solution to many practical problems and still - they have not received in the past the amount of research interest that they deserve. It is the aim of the present book to improve this situation. The book originated from the lectures and seminars presented at the course on "Po1ycrystall i ne Semi conductors - Physical Properties and Applications" of "the International School on Materials Scien ce and Technology, hel d at the Centre for Sci entifi c Culture "Ettore Majorana" in Erice, Italy, July 1-15, 1984."

This volume contains the proceedings of the International Winter School on Electronic Properties of High Temperature Superconductors, which was held March 3-10, 1990, in Kirchberg (Tyrol), Austria. This course was a sequel to three meetings on the subject of conducting polymers held there one, three and five years previously. The new topic was taken up since many of the scientists working on conducting polymers are now also actively interested in high-Tc superconductors, a research area that continues to develop at a remarkable pace. There have been numerous specialist conferences on high-Tc superconductors since their discovery by Bednorz and Muller in 1986. The Kirchberg meetings are intended as a school where experienced scientists from universities, research laboratories, and industry have the opportunity to discuss their most recent results, and where young scientists and students can learn about the present status of research in this field. The 1990 winter school was again organized in cooperation with the "Bundesministerium fur Wissenschaft in Austria and with the "Bundesministerium fur Forschung und Forschung" und Technologie" in the Federal Republic of Germany. The scientific interest was focused on the electronic structure of high-Tc superconductors and related compounds. At the beginning of each session, tutorial contributions were presented as an introduction for non-specialists. These were followed by research contributions elucidating the current state of our know ledge about high-Tc superconductors.

This volume contains the proceedings of the first ISSP International Symposium on the Physics and Chemistry of Organic Superconductors, which was held at the Komaba Eminence Hotel in Tokyo, August 28-30, 1989. This symposium was attended by 205 scientists from 12 countries. In total 106 papers were presented: 61 as posters, and 39 original papers and 6 review papers in oral sessions. Of these, 102 papers are included in these proceedings. These contributions cover the interdisciplinary field of physics and chemistry of organic superconductors with particular emphasis on the following subjects and materials: - superconducting properties, - spin density waves, - electronic and structural properties, - TMTSF salts and their derivatives, - BEDT -TTF salts and their derivatives, - metal coordinated organic conductors. The contributions to this volume are arranged in 11 categories. The Organizing Committee would like to acknowledge all participants, who contributed to the great success of this symposium on a growing field in both physics and chemistry. The editors express their gratitude to the members of the Organizing and Executive Committees for their cooperation. We also wish to thank Dr. H. Lotsch of Springer-Verlag for his management of the publication and Miss S. Shibata for her assistance in editing this volume.

The renaissance of magnet technology started in the early 1950s with the establishment of high-energy accelerators. About a decade later in 1961, or fifty years after the discovery of superconductivity, high-field superconducting laboratory magnets became a reality. Conventional still the major beam-handling and experimen electromagnets, which are tal devices used in laboratories, operate at zero efficiency. To generate high magnetic fields in a useful volume, considerable amounts of power are needed. Superconducting d. c. magnets do not require any power at all. It is somewhat depressing to note that, sixty years after the first superconductor was tested, the experimental d. c. superconducting mag net is still the only large-scale equipment operated in laboratories. Al though there has been considerable activity in the area of superconduc tivity, superconductors are used on quite a modest scale in electronic and quantum devices, in medicine and biology, and in physical experi ments where high magnetic fields are essential. It is only recently that Type II superconductors have been introduced in power engineering (power generation, storage and transport) to replace pulsed accelerator magnets; for fast and economical transportation vehicles (levitated trains) where superconductors may ultimately replace the wheel; to make new means of en rgy generation economically feasible, such as in magneto hydrodynamics and in fusion reactors; and for high-efficiency electric motors. High-field superconducting magnets are being proposed for de salination of seawater, for magnetic separation in the mining industry, for cleaning polluted water, and for sewage treatment."

Recent research on superconductors with high critical temperature has led to results that were not available when the original German edition was prepared but could be included in the present English edition. This concerns materials based on bismuth and thallium, as well as measurements of low microwave loss. The author would like to thank Mr. A. H. Armstrong for translating the book from German to English in a very dedicated and competent manner. Thanks are also due once again to Springer-Verlag for their generous support and cordial cooperation. Bad Salzdetfurth September 1989 Johann H. Rinken Preface to the German Edition The development of materials which lose their electrical resistance when cooled, even before reaching the boiling point of liquid nitrogen, has considerably in creased the interest in superconductor technology, and with it superconductor electronics. This development had not been foreseen when work on the present book started, just over a year ago. Nevertheless, recent results of research on materials with high critical temperature are included to the extent that they seem to be confirmed and to be of interest to superconductor electronics. The present book deals with the physical and technological foundations of superconductor electronics so far as they must be known in order to under stand the principal modes of operation of superconductor electronics components.

The sixth Taniguchi Symposium on the Theory of Condensed Matter was held between 14-18 November 1983 at Kashikojima. Japan. During the Symposium, about twenty participants lived together and discussed the magnetic super conductors and related problems in an active and friendly atmosphere. This volume contains the papers presented at this Symposium. A strong impetus for organizing a Symposium of this subject is afforded by recent intense interest and accumulated information on magnetic and other novel superconductors newly discovered, and indeed the Symposium has pro duced many excellent contributions to this very exciting field of condensed matter theory, as reported in this volume. In order to give the readers a general outline of the subject, a brief sketch of the problem is made in the Introduction. Then the remainder of this volume is divided into four Parts and an Appendix. Part I is devoted to di scuss ions on several aspects of ferromagnetic superconductors includ ing superconductivity in heavy fermion systems. Part II treats problems on anti ferromagnetic superconductors. In Part III three papers on organic supercon ductors are presented. Part IV includes discussions on the exotic supercon ductors. The Appendix is concerned with the new research project towards high Tc superconductors in Japan. The last but not least remark is to mention the activity of the Taniguchi Foundation whose support makes this Symposium possible. For many years Mr."

The recent discovery of high-temperature superconductivity in copper based oxides is an event of major importance not only with respect to the physical phenomenon itself but also because it definitely shows that solid state chemistry, and especially the crystal chemistry of oxides, has a crucial place in the synthesis and understanding of new materials for future appli cations. The numerous papers published in the field of high Tc supercon ductors in the last five years demonstrate that the great complexity of these materials necessitates a close collaboration between physicists and solid state chemists. This book is based to a large extent on our experience of the crystal chemistry of copper oxides, which we have been studying in the laboratory for more than twelve years, but it also summarizes the main results which have been obtained for these compounds in the last five years relating to their spectacular superconducting properties. We have focused on the struc ture, chemical bonding and nonstoichiometry of these materials, bearing in mind that redox reactions are the key to the optimization of their supercon ducting properties, owing to the importance of the mixed valence of copper and its Jahn-Teller effect. We have also drawn on studies of extended defects by high-resolution electron microscopy and on their creation by ir radiation effects."

The structural. electronic and lattice properties of superconducting ternary com pounds are the subject of this Topics volume. Its companion volume (Topics in Cur rent Physics. Volume 34) deals primarily with the mutual interaction of supercon ductivity and magnetism in ternary compounds. These two volumes are the culmination of a project. started nearly two years ago. that was inspired by the intense re search effort. both experimental and theoretical. then being expended to explore and develop an understanding of the remarkable physical properties of ternary super conductors. Research activity on this subject has increased in the meantime. The interest in ternary superconductors originated in 1972. when B.T. Matthias and his co-workers first discovered superconductivity in several ternary molybdenum sulfide compounds that had been synthesized in 1971 by R. Chevrel. M. Sergent. and J. Prigent. The superconducting critical temperature Tc of one of the compounds. PbMo S * was reported to be ~ 15 K. This value is sufficiently high that there was g 6 (and still is) reason to expect that other ternary compounds would be found with superconducting transition temperatures rivaling those of the A15 compounds. of which Nb Ge has the record high Tc of 23 K. The interest in ternary superconductors 3 received further impetus when several of the ternary molybdenum sulfides were found to have exceptionally high upper critical magnetic fields. some of them in the neighborhood of 50 Tesla or more. An immense amount of research on ternary molybdenum chalcogenides then followed.

The book provides an in-depth understanding of the fundamentals of superconducting electronics and the practical considerations for the fabrication of superconducting electronic structures. Additionally, it covers in detail the opportunities afforded by superconductivity for uniquely sensitive electronic devices and illustrates how these devices (in some cases employing high-temperature, ceramic superconductors) can be applied in analog and digital signal processing, laboratory instruments, biomagnetism, geophysics, nondestructive evaluation and radioastronomy. Improvements in cryocooler technology for application to cryoelectronics are also covered. This is the first book in several years to treat the fundamentals and applications of superconducting electronics in a comprehensive manner, and it is the very first book to consider the implications of high-temperature, ceramic superconductors for superconducting electronic devices. Not only does this new class of superconductors create new opportunities, but recently impressive milestones have been reached in superconducting analog and digital signal processing which promise to lead to a new generation of sensing, processing and computational systems. The 15 chapters are authored by acknowledged leaders in the fundamental science and in the applications of this increasingly active field, and many of the authors provide a timely assessment of the potential for devices and applications based upon ceramic-oxide superconductors or hybrid structures incorporating these new superconductors with other materials. The book takes the reader from a basic discussion of applicable (BCS and Ginzburg-Landau) theories and tunneling phenomena, through the structure and characteristics of Josephson devices and circuits, to applications that utilize the world's most sensitive magnetometer, most sensitive microwave detector, and fastest arithmetic logic unit.

This Topics in Current Physics (TCP) Volume 34 is concerned primarily with super- conductivity and magnetism, and the mutual interaction of these two phenomena in ternary rare earth compounds. It is the companion of TCP Volume 32 - Superconduc- tivity in Ternary Compounds: Structural, Electronic and Lattice Properties. The interplay between superconductivity and magnetism has intrigued theoreticians and experimentalists alike for more than two decades. V. L. Ginzburg first addressed the question of whether or not superconductivity and ferromagnetism could coexist in 1957, and B. T. Matthias and coworkers carried out the first experimental inves- tigations on this problem in 1959. The early experiments were made on systems that consisted of a superconducting element or compound into which small concentrations of rare earth impurities with partially-filled 4f electron shells had been intro- duced. These dilute impurity systems were chosen because the scattering of conduc- tion electrons by parama9. netic rare earth impurity ions usually has a strong de- structive "pa i r breaking" effect on superconducti vity, typi ca lly drivi ng the super- conducting transition temperature to zero at impurity concentrations of only a few atomic percent. Unfortunately, analysis of these early experiments was complicated by clustering and/or the formation of short range or "glassy" types of magnetic order so that definitive conclusions regarding the coexistence of superconductivity and magnetism could not be reached.

In this text experts review experimental studies that directly reveal the relationship between the atomic structure and physical behavior of high-Tc superconductors. The thorough discussion centers on twins, twin boundaries, the vortex lattice, and magnetic and mechanical properties in connection with structural imperfections. Particular attention is paid to the role of the oxygen atom in the Y-Ba-Cu-O and La-Cu-O species. The experimental methods evaluated include electron and X-ray diffraction, electron microscopy, and M-ssbauer spectroscopy. This book makes extraordinarily valuable data obtained at the Institute of Solid State Physics at Chernogolovka accessible to the wider international community of researchers in superconductivity.

During the past thirty years considerable efforts have been made to design the synthesis and the study of molecular semiconductors. Molecular semiconductors - and more generally molecular materials - involve interactions between individual subunits which can be separately synthesized. Organic and metallo-organic derivatives are the basis of most of the molecular materials. A survey of the literature on molecular semiconductors leaves one rather confused. It does seem to be very difficult to correlate the molecular structure of these semiconductors with their experimental electrical properties. For inorganic materials a simple definition delimits a fairly homogeneous family. If an inorganic material has a conductivity intermediate between that of an 12 1 1 3 1 1 insulator " 10- n- cm- ) and that of a metal (> 10 n- cm- ), then it is a semiconductor and will exhibit the characteristic properties of this family, such as junction formation, photoconductivity, and the photovoltaic effect. For molecular compounds, such simplicity is certainly not the case. A huge number of molecular and macromolecular systems have been described which possess an intermediate conductivity. However, the various attempts which have been made to rationalize their properties have, more often than not, failed. Even very basic electrical properties such as the mechanism of the charge carrier formation or the nature and the density ofthe dopants are not known in detail. The study of molecular semiconductor junctions is very probably the most powerful approach to shed light on these problems.

"Integrated 60GHz RF Beamforming in CMOS "describes new concepts and design techniques that can be used for 60GHz phased array systems. First, general trends and challenges in low-cost high data-rate 60GHz wireless system are studied, and the phased array technique is introduced to improve the system performance. Second, the system requirements of phase shifters are analyzed, and different phased array architectures are compared. Third, the design and implementation of 60GHz passive and active phase shifters in a CMOS technology are presented. Fourth, the integration of 60GHz phase shifters with other key building blocks such as low noise amplifiers and power amplifiers are described in detail. Finally, this book describes the integration of a 60GHz CMOS amplifier and an antenna in a printed circuit-board (PCB) package.

The characterization of epitaxial layers and their surfaces has benefitted a lot from the enormous progress of optical analysis techniques during the last decade. In particular, the dramatic improvement of the structural quality of semiconductor epilayers and heterostructures results to a great deal from the level of sophistication achieved with such analysis techniques. First of all, optical techniques are nondestructive and their sensitivity has been improved to such an extent that nowadays the epilayer analysis can be performed on layers with thicknesses on the atomic scale. Furthermore, the spatial and temporal resolution have been pushed to such limits that real time observation of surface processes during epitaxial growth is possible with techniques like reflectance difference spectroscopy. Of course, optical spectroscopies complement techniques based on the inter action of electrons with matter, but whereas the latter usually require high or ultrahigh vacuum conditions, the former ones can be applied in different environments as well. This advantage could turn out extremely important for a rather technological point of view, i.e. for the surveillance of modern semiconductor processes. Despite the large potential of techniques based on the interaction of electromagnetic waves with surfaces and epilayers, optical techniques are apparently moving only slowly into this area of technology. One reason for this might be that some prejudices still exist regarding their sensitivity."